If I want to copy URL of current web page i have select the address from address bar and press "Ctrl + C". But is there any way, if no text is selected on a web page, when I press "Ctrl + C", it will copy URL of current place to clipboard. any firefox, chrome extensions or Greasemonkey script will do

Dunno, I haven't used FF since it came out years ago :D I guess you will find some.‌​..
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slhck♦May 2 '11 at 12:22

I realize that this post is old but I just stumbled across it and, as the developer of URL Copy, I wanted to let you know that today it is known as Template and does so much more than it used to and is highly customizable but maintains the simplicity of the original extension. I was pleasantly surprised to find this answer and hope you'll check out Template in the Web Store or GitHub, if you prefer.
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AlasdairMar 8 '12 at 13:13